The bicycle frame installed at a top of a car has two basic types. One is an integral car top carries and another is a detached front wheel carrier. Both are fixed on a car top in advance. In using, the user must lift the bicycle to the car top for installation and then the bicycle is tightened. However it is often that it is too high to be achieved by users so that a platform is used.
However these prior arts have the following defects. The bicycle is longitudinally arranged (parallel to the moving direction of the car) and is stand on the car top. The supporting rod for bicycle body is tilt with a small angle and the weight center of the bicycle is high so that the user will worry about the safety in driving. Furthermore, the arrangement of the bicycle is confined by the width of the top side of the car.
Moreover, the detached front wheel car top carrier has the defect that the front wheel must be detached, but this is inconvenient. Moreover, the front wheel occupies a space of the interior of the car.
Therefore, there is a demand for a novel design which can improve above mentioned defects.